| 摘要 |
PURPOSE: To shorten a term for manufacture by manufacturing an equilateral trapezoid bar and cut a vane material at right angle to a symmetrical plane surface of the bar. CONSTITUTION: On an assumption that the number of vane of a vane array is n, an equilateral trapezoidal bar B whose angleαof vertex of the bar B is equal to 2π/n is manufactured by milling. A vane material A is cut out from a right angled direction to a symmetrical plane surface of the bar B. Outline parts 11, 12 of a head of the vane material A and outline parts 14, 15, 16 of a lag of the vane material A are processed into a final size, then mutual edges of the head are confronted and welded to form a vane array. Thereby, a term for manufacture can be shortened. |
